Autoglym Ultimate Screenwash is a highly concentrated formula screen wash for cars ideal for winter weather down to -45 degrees, keeping your windscreen ice-free This windscreen washer fluid is suitable for all seasons. The screenwash concentrate solution can be diluted to make up to 8 litres of premium screenwash and will easily cut through road grime, insect remains and anything else that may end up on your windscreen Suitable for all wash jet types and well as headlight wash units and is safe on paintwork and trim For the Optimum clean we would recommend to use Ultimate Screenwash at a dilution rate of 1:9. Optimum clean recommended for best performance in summer and spring, or autumn above -3°C Maximum Dilution 1:15 for -1°C. Optimum Clean Dilution 1:9 for -3°C. Winter Dilution 1:4 for -6°C. Severe Winter Dilution 1:2 for -14°C. Extreme Winter 1:1 for -25°C. No Dilution 1:0 for -45°C.